A hysteresis current control method for active power filter with lower switching losses

A new hysteresis current control method for APF(active power filter) with lower losses and high efficiency is suggested. The control circuit changes the distribution of the switching number according to the output current of APF. The switching losses of new method are lower 20% than that of conventional hysteresis control method without the influence of control precision. The adjustment of hysteresis band width considers both the absolute value of the overall three-phase current and the each phase current. The related deductions and formulations are presented. Computer simulation is conducted on a testing system of PSCAD/EMTDC program. The results show that the new method can effectively reduce the switching losses under the same performance of current tracking.